As the privacy
controversy around full-body security scans begins to simmer,
it’s worth noting that courthouses
and airport
security checkpoints aren’t the only places where backscatter x-ray
vision is being deployed. The same technology, capable of seeing through
clothes and walls, has also been rolling out on U.S. streets.

American Science & Engineering, a company based in
Billerica, Massachusetts, has sold U.S. and foreign government agencies
more than 500 backscatter x-ray scanners mounted in vans that can be driven
past neighboring vehicles to see their contents, Joe Reiss, a vice president
of marketing at the company told me in an interview. While the biggest
buyer of AS&E’s machines over the last seven years has been the Department
of Defense operations in Afghanistan and Iraq, Reiss says law enforcement
agencies have also deployed the vans to search for vehicle-based bombs
in the U.S.

“This product is now the largest selling cargo and vehicle inspection
system ever,” says Reiss.

Here’s a video of the vans in action.

The Z Backscatter Vans, or ZBVs, as the company calls them, bounce a
narrow stream of x-rays off and through nearby objects, and read which
ones come back. Absorbed rays indicate dense material such as steel. Scattered
rays indicate less-dense objects that can include explosives, drugs, or
human bodies. That capability makes them powerful tools for security, law
enforcement, and border control.

It would also seem to make the vans mobile versions of the same scanning
technique that’s riled privacy advocates as it’s been deployed in airports
around the country. The Electronic Privacy Information Center (EPIC) is
currently suing the DHS to stop airport deployments of the backscatter
scanners, which can reveal detailed images of human bodies. (Just how much
detail became
clear last May, when TSA employee Rolando Negrin was charged with assaulting
a coworker who made jokes about the size of Negrin’s genitalia after Negrin
received a full-body scan.)

“It’s no surprise that goverments and vendors are very enthusiastic
about [the vans],” says Marc Rotenberg, executive director of EPIC. “But
from a privacy perspective, it’s one of the most intrusive technologies
conceivable.”

AS&E’s Reiss counters privacy critics by pointing out that the ZBV
scans don’t capture nearly as much detail of human bodies as their airport
counterparts. The company’s marketing materials say that its “primary purpose
is to image vehicles and their contents,” and that “the system cannot be
used to identify an individual, or the race, sex or age of the person.”

Though Reiss admits that the systems “to a large degree will penetrate
clothing,” he points to the lack of features in images of humans like the
one shown at right, far less detail than is obtained from the airport scans.
“From a privacy standpoint, I’m hard-pressed to see what the concern or
objection could be,” he says.

But EPIC’s Rotenberg says that the scans, like those in the airport,
potentially violate the fourth amendment. “Without a warrant, the government
doesn’t have a right to peer beneath your clothes without probable cause,”
he says. Even airport scans are typically used only as a secondary security
measure, he points out. “If the scans can only be used in exceptional cases
in airports, the idea that they can be used routinely on city streets is
a very hard argument to make.”

The TSA’s official policy dictates that full-body scans must be viewed
in a separate room from any guards dealing directly with subjects of the
scans, and that the scanners won’t save any images. Just what sort of safeguards
might be in place for AS&E’s scanning vans isn’t clear, given that
the company won’t reveal just which law enforcement agencies, organizations
within the DHS, or foreign governments have purchased the equipment. Reiss
says AS&E has customers on “all continents except Antarctica.”

Reiss adds that the vans do have the capability of storing images. “Sometimes
customers need to save images for evidentiary reasons,” he says. “We do
what our customers need.”